1. Field of the Invention
This invention relates to a semiconductor device assembly and more specifically to a thin type semiconductor integrated circuit device assembly.
2. Description of the Prior Art
Recently, the demand for thin type semiconductor integrated circuit chip assembly has increased because thin type electronic equipment, such as IC cards, have become more widely used.
The use of potting resin sealed plastic packages is well known as an assembly technique for such chips. In this type assembly, liquid plastic resin is deposited at the periphery of a chip. The electrodes of the chip are connected to a plurality of leads formed and arranged on a tape. The liquid plastic resin fixes the connection between the leads and the electrodes and protects the assembly from mechanical stress and various environmental conditions.
With this technique, since the resin is deposited, it is difficult to control the thickness of the assembly. Moreover, a thin film coating of less than 1 mm for large sized chips requires resin viscosity adjustment and thus, there are limits to the resins which can be used. Resins which prevent moisture penetration generally cannot be used to prepare thin film coatings of less than 1 mm.
Ceramic packages and molded resin sealed plastic packages have also been used for the assembly of semiconductor integrated circuit chips. However, such packages usually cannot absorb external forces and are more likely to be damaged, since they are hard type packages and are fragile when subjected to even slight deformations. For this reason, it is difficult to produce and use assemblies of less than 1 mm thickness for large sized chips.